The UK’s drinking water is contaminated with cocaine, or so the headline writers would have you believe. When you delve closer, you find that the actual story is that water from just four sites that was tested by the Drinking Water Inspectorate was found to contain very low levels of benzoylecgonine, the principal human metabolite of cocaine.

It seemed that some journalists wanted us to think that our drinking water is dangerous because it contains cocaine. In fact, benzoylecgonine is far less toxic than cocaine, with doses 60-fold higher than those of cocaine still producing only mild effects.

It is strange that the report outlining this finding was published in September 2013 but suddenly became hot news in May, 2104. Picked up and dispersed rapidly by a number of daily newspapers it made headlines around the world. In fact, benzoylecgonine was found as part of a broad study to see how effective wastewater treatment plants were in removing a whole range of pharmaceuticals.

Only six compounds were detected after treatment, the other five being caffeine, carbamazepine, carbamazepine epoxide, ibuprofen and naproxen. However, the amounts found in water were miniscule: “of the order of thousands of times below the level associated with adverse effects in animals and hundreds of thousands of times below human therapeutic doses,” according to Sue Pennison from the DWI.

In recent years, a number of reports have shown that rivers and other untreated water sources are contaminated with drugs that are flushed away or escape through drains. But there really is nothing to worry about as far as drinking water is concerned. “The study which looked at worst case scenarios is reassuring in that it demonstrated that water treatment was generally very effective in the removal of a number of pharmaceuticals which were detected in untreated river water in trace amounts,” Pennison continued.